Disazo dyes containing a diphenylurea nucleus



Patented May 26, 1925.

UNITED STA ES I 1,538,934 PATENT OFFICE.

LEON w. GELLER, or HAMBURG, NEW YORK, ASSIGNOR ro NATIONAL ANILINE & CHEMIGAL 00. me, on NEW YORK, N. Y., A CORPORATION or NEW Yonx.

DISAZO DYES CONTAINING A DIPHENYLUREA NUCLEUS.

- No Drawing.

To all whom it may concern:

- Be it known that I, LEo W. GELLER, a citizen of Rumania, residing at Hamburg, in the county of Erie, State of New York, have invented certain new and useful Imrovements in Di'sazo Dyes Containing a iphenylurea Nucleus; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.'

This invention relates to themanufacture and production of-new azo dyes which are of value for dyeing unmordanted cotton. They also dye wool, silk and other fibres. The dyed fabrics, or other material, dyed with the new dyestuffs also form a part of the present invention.

The new dyestufl's can be obtained by converting into a urea compound the aminoazo dyes obtainable by combining one mol of diazotized 3-amino-et-methylbenzene-l-sulfonic acid with one mol of 4-alkoXy-3-amino-1- methylbenzene, e. g., 4-meth'oxy 3-amino-lmethylbenzene, lr-ethoxy-3-amino-1-methylbenzene, etc. The urea compound is produced in the usual way by treating the a1ni- .noazo dyes thus obtainable, said aminoazo compounds being hereinafter denoted and referred to as 2.2-dimethyl-fi-alkoxyi-aminoazobenzene-5-sulphonic acid, with phosgene in the presence of substances adapted to absorb hydrochloric acid such as, for instance, sodium carbonate.

The following specific example will further illustrate the invention, but it isunderstood that the invention is not limited there to; The parts are by weight.

Example: 187 parts (one mol) of 3-aminol-methylbenzene-l-sulfonic acid are suspended in about 1500 parts Water containing abut 235 parts hydrochloric acid (20-B.)

alcohol, and soluble in concentrated sulfuric Application filed April 28, 1924. Serial No. 709,686.

and 500 parts of ice, and are diazotized in the usual manner with the aid of about 70 parts sodium nitrite previousl dissolved in about, 250 parts water. To t cold diazo solution thus obtained, and maintained at a temperature of 0 to 5 0., there is added, while stirring, acold solution of 137 parts (one mol) of l-methoxy-3-aminoe1-methylbenzene dissolved in about 3000 parts water and 136 parts hydrochloric acid (20 B.).

The resulting mixture is then neutralized by the addition of sodium carbonate, and about 15 to 20 parts of sodium acetate subsequently added. The mixture is stirred until the combination is completed. When the combination is complete, the aminoazo compound is precipitated by acidifying the solution by the addition-of hydrochloric acid and the precipitate isolated by filtration or other suitable means.

The aminoazo com ound thus obtained, and which is denote ferred to as 2.2-dimethyl-5-methoxy-4-aminoazobenzene-5'-sulfonic acid, is dissolved in about 25,000 parts water containing about 170 parts of sodium carbonate, and a current of phosgene is slowly introduced at ordinary temperature into the well stirred solution until the 1 aminoazo compound is converted into the urea compound. The solution is kept alkaline throughout the reaction by the further addition, if necessary, of sodium carbonate. The reaction is fin ished when a test sample of the solution acidified with hydrochloric acidproduces only. a faint pink color when spotted on white filter-paper. When the'reaction is complete, the dyestufi is salted out, isolated,

pressed 'anddried.

The new dyestuff thus obtained, in the form of its sodium salt,.has most probably the following formula:

CH; CH;

CH: oiNa acid with a dark bluish red color which on addition of ice produces a reddish brown precipitate. -Upon reduction with stannous chloride and hydrochloric acid it yields 3- and hereinafter re- 1 add aminoi-methylbenzene sulfonic acid, 2.2 dim'ethoxy- LA-diamino-5.5'-dimethyl d1- phenyl urea which by hydrolysis may be further decomposed into carbonic acid and 2.5-diamino-4-methoxytoluene. It dyes unmordanted cotton from a neutral bath yield ing yellow shades of excellent fastness to washing and to light and which are capable of being discharged to a white by discharging agents such as sodium hydrosulfiter I Analogous dyestufi's possessing similar qualities are produced by treating 2.2-

$03M 7 where R. denotes an alkyl group, suchas CH ,'C H etc., being ureas of amlnazo compounds obtainable bycoupling 'diazotized 3-amino-4-methylbenzene 1 sulfonic zene, yielding upon reduction with stanous chloride and hydrochloric acid, 3-amino-4- methylbenzcne sulfonic acid and 2.2-dialkoxy 4.4'-diamino 5.5 dilnethyldiphenyl urea which upon hydrolysis is further decomposed into 2.5-diamino-4-alkoxytoluene and carbonic acid; said azo dyestuffs in the into 4-alkoXy-3-amino-l-methylbendimethyl-5-ethoxy-l-a1hino azobenzene 5 sulfonic acid in a similar manner with phosene.

In the specification and claims it will be understood thatthe term alkoxy denotes and includes the alkyl derivatives of a hydroxyl group, such as -OCH (methoxy), OC H (ethoxy), etc.

claim:

. 1. As new products, the having in the shape of their the following probable formula:

shape of their dry and pulverized sodium.

salts being yellowish brown powders soluble in water with a yellow color, and soluble in concentrated sulfuric acid with a bluish red olor which on dilution with ice produce a reddish brown precipitate; and dyeing unmordanted cotton yellow shades which are capable of being discharged to a white by the action of sodium hydrosulfite.

2v As a new product, the azo dyestufi' havazo dyestuffs sodium salts v ing in the shape of its sodium salt the following probable formula:

/\\N1N I I WMN NHbOLHN- som cm OQ, 03m

and obtainable bytreating.2.2'-dimethyl-5- methoxy-et-aminoazobenzene-5'-sulfonic acid composed into 2.5-diaminoi-methoxytoluene and carbonic acid; and said dyestufi' dyel'ng unmordanted cotton yellow shades which are capable of being discharged to a white by the action of sodium hydrosulfite.

3. Materials dyed with the dyestufls of claim 1. '1

4. Materials dyed with the dyestuff of claim 2.

In testimony whereof I aflix my signature.

LEON WV. (SrELLER. 

